anesthes

iTrader: (12)

So I bought this 5.3 the other day. I didn't pay much for it because I didn't hear it run. Has 130k.

Anyway, so I got it on the stand. I ripped the exhaust manifolds off, starter, accessories, etc. The kid left the torque converter on, so I went to remove that. I noticed I could rotate the motor by hand easily.

I took the torque converter off. I can grab either the flex plate, or the crank pulley with two hands and completely rotate the motor over.

Now considering everything I'm used to is a PITA to rotate even with a rotating tool that hooks on the flywheel, I'm kinda thinking this thing has very low compression?

Or it's got the lowest drag piston rings on the planet.

But since I don't know jack about LSx stuff, I figured I'd ask.

I paid $150 for this motor complete. I figure even if it needs a rebuild, that's a good price for a core.

-- Joe

grngryoutmyway

iTrader: (1)

My LS1 I know was running when pulled. It seemed pretty easy to turn with the heads on but I don't know that I could have done it by hand. With the heads off sure. After rebuild it was much tougher, but I also bumped compression and some other stuff.

Compression is a little lower on the truck motors, depending on the heads I think around 9.5-1. You sure the heads weren't off and not properly put back on or something like that?

QwkTrip

iTrader: (22)

It is easy to tun with all the plugs out. Just friction at that point, no compression.

406TPI

iTrader: (1)

Mine rolls over very easy with the plugs out. No problem grabbing the crank pulley and spin it over and it's a very low mile factory crate motor.

anesthes

iTrader: (12)

Plugs are all in.. I'll take a video later for you guys to see.

If I have time I'm going to put the starter on it and do a compression test. I'm guessing something north of 140psi is stock for a early 5.3?

I'm thinking of just getting a 5.7 rotating assembly and boring the block. An iron block LS1 would be a nice boost motor.

-- Joe

grngryoutmyway

iTrader: (1)

Just FYI if your going to start rebuilding/machining ect Summit does have the GM 5.3 bare block for $300

https://www.summitracing.com/parts/s...Fc5ZhgodZEAIQQ

Good deal if you need one.

anesthes

iTrader: (12)

I saw that, but it's $150 to ship it to my door, then I gotta do freeze plugs, cam bearings, galley plugs, and all that and final hone.

It's cheaper to machine the one I have.


I gotta do more reading though. I've not done any LSx stuff. I might be making some assumptions of what it's capability is..

-- Joe

anesthes

iTrader: (12)

here

grngryoutmyway

iTrader: (1)

Do you feel air coming out of anywhere besides the exhaust ports? That seems way too easy.

anesthes

iTrader: (12)

No, but I need to get someone to turn it while I check.

If I have time tomorrow night I'll do a compression test but, yeah. I was bummed. But for $150 I can't gripe.

I figure I could either make a low boost 5.3, or maybe a 400hp naturally aspirated 5.7 out of it.

-- Joe

QwkTrip

iTrader: (22)

That engine is toast.

anesthes

iTrader: (12)

Yeah that's kinda what I was thinking.

-- Joe

Pocket

iTrader: (24)

Yeah that was too easy to spin

I can spin most used truck motors over by grabbing the balancer by hand, but its slow and I have to let compression bleed off as it turns

anesthes

iTrader: (12)

Well, I guess It will be a core for a future project.

-- Joe

Pocket

iTrader: (24)

For $150 youve got in it, you could turn it in to most rebuilders and make money. They're cake to overhaul, so dont sweat it

anesthes

iTrader: (12)

I have not done one before, but I figure it's time to start. Really thinking of doing a 5.7 build. I here you can bore them out and stick ls1 rotating assembly.

-- Joe